A hydraulic system for an agricultural application typically includes one or more hydraulic cylinders which receive pressurized hydraulic fluid from a pressure source, such as a hydraulic pump within an agricultural tractor. In the case of a single cylinder, the hydraulic cylinder includes a pair of fluid lines which are in communication with chambers on respective sides of a piston attached to a ram. The fluid lines are coupled with a dual outlet hydraulic bank located at the back of the tractor and operated from within the cab. In the case of multiple hydraulic cylinders coupled together, each of the cylinders receive pressurized fluid in a parallel or series manner, depending upon the particular application. Hydraulic cylinders of this type are generally useful for lifting heavy loads and the like.
It is also possible to balance a load such as a structural member pivotally connected to another frame member through the use of springs, counter weights, etc. In the case of springs, one or more springs may be placed between the load to be balanced and the pivotally coupled frame member on opposite sides of the pivot location to keep the load in a generally centered orientation relative to the frame member. Spring configurations of this type may be suitable for balancing loads, but may also be bulky and impractical in terms of space requirements. Further, such spring arrangements offer some resistance to relative movement between the structural members, but do not prevent movement therebetween.
What is needed in the art is a hydraulic system which can be used, e.g., with an agricultural mower, and provides the dual functionality of both balancing as well as locking a load relative to a frame member.